1. Field of the Invention
The invention is in the field of blood sample acquisition and testing. In particular, the invention is directed to a sensor strip used in a device that performs both a lancing operation to acquire a blood sample and a measurement operation on the sample in one user-initiated step. The strip is provided with a plurality of test sites, and may be wound on a supply wheel and fed through the device between the supply wheel and a take-up wheel, so that a single strip may be used to obtain a plurality of measurements.
2. Description of the Related Art
Self-monitoring of blood glucose generally requires the user to extract a volume of capillary blood and place it on a disposable element for analysis. Devices for lancing a subject at an extraction site to obtain a small quantity of blood for testing on a test strip are known in the prior art. For example, U.S. Pat. No. 6,558,402, which is incorporated by reference, discloses a lancer having suitable mechanisms for piercing a subject's skin and obtaining a sample.
Test strip sensing elements using amperometric and other techniques for determining the concentration of blood glucose in a blood sample are known in the prior art. U.S. Pat. Nos. 6,143,164, and 5,437,999, incorporated by reference herein, each disclose examples of test strip construction for electrochemical measurement of blood glucose.
The integration of lancing and sensing would be a desirable advance in the self-monitoring of blood glucose. U.S. patent application Ser. No. 12/502,594, filed Jul. 9, 2009, describes such a “two-in-one” device, wherein a single test strip contains a plurality of test sites, which can be advanced automatically through a testing device. In this context, it would be desirable to have a layout of electrodes and contact pads on a test strip to permit automatic advancement of the strip through the device, that would account for variations in alignment, and to eliminate transient signals as the strip is indexed through different stop points in the lancing/sensing process and on to the next test position on the strip.